12 ALASKAN GLACIER STUDIES by Brooks in 1899 * and by Moffit and Capps in 1908,2 during -which time they have apparently been retreating uniformly. Logan Glacier, northwest of Mt. St. Elias at the-headwaters of the Chitina Eiver, was discovered by the Boundary Survey in 191& when it was advancing. Glaciers of the Wrangell Mountains. One of the most compact systems of Alaskan glaciers is that upon the Wrangell Mountains, 10,000 to 16,000 feet, where the Drop,. West, Copper, Jacksina, Nabesna, Chisana, and minor glaciers flow northward, while the Frederika, Nizina, Rohn, Regal, Kennicott, Kuskulana, Khivesna, Long, Cheshnina,. Chetaslina, Dadina, Nadina, and others flow south. Nabesna Glacier is 55 miles long, and 2£ miles wide. Kennicott Glacier is 19 miles long and 2 to S miles wide. These glaciers have been partly or wholly described and mapped by Hayes in 1891, Rohn in 1899, Schrader and Spencer in 1900, Mendenhall and Schrader in 1902, Moffit, Maddren, and Capps in 1907 and 1908, and Dunn in 1908,3 the latter being the first to ascend the 14,000 foot, snow-sheathed active cone of Mt. Wrangell. The snowfields of these glaciers nearly cover the WrangeD Mountains, which include four volcanoes, Mts. Wrangell, Drum, Sanford, and Blackburn. The lower portion of Kennicott Glacier and several adjacent ice tongues were accurately mapped in 1908 by D. C. Witherspoon and described by F. H. Moffit and S. R. Capps.4 In 1911 and 1912 several of these glaciers were traversed by Miss Dora Keen in her ascent of Mt. Blackburn.6 The radial consequent glaciers of Mt. Sanford are notable, as is the unsymmetrical glacier drainage development on Mt. Wrangell, where it has been supposed that the greater heat on the steeper west side of this active volcano results in melting away the western glaciers. Some of the recent lavas overlie glacial deposits but have been themselves glaciated since cooling. Nabesna and Chisana Glaciers, northeast of Mt. Wrangell, were retreating in 1898, but Nizina and Russell Glaciers advanced between 1899 and 1908. Frederika Glacier was advancing when seen by Hayes in 1891 but had begun to recede before the visit of Moffit and Capps in 1908, while the small glacier opposite it was then advancing. i Brooks, A. H., 21st Ann. Kept., U. S. Geol. Survey, 1899-1900, Part H, p. 364 and PI. I. » Capps, S. R., Journ. Geol., VoL XVHI, 1010, pp. 48^65. • Hayes, C. W., Nat. Geog. Mag., Vol. IV, 1892, pp. 168-154, and map, PL 20. Schrader, F. C., 20th Ann. Rept., U. S. Geol. Survey, 1900, p. 377. Rohn, Oscar, Copper River Exploring Expedition, Narratives of Explorations in Alaska, Washington, 1900, pp. 791, 799-801, 820; 21st Ann. Rept, U. S. Geol. Survey, Part n, 1900, pp. 406-407, and map, PL LH Schrader, F. C. and Spencer, A. C., House Doc. 548, 56th Congress, 2d Session, Washington, 1900, pp. 31-32, 58-61, 76-81 and map, PI. II. Mendenhall, W. C. and Schrader, P. C., Professional Paper 15, U. S. Geol. Survey, 1903, PI. HI. MendenhalL W. C., Professional Paper 41, U. S. Geol. Survey, 1905, pp. 18, 62-72, 88-90, and map, Pis. XIX and XX. Mendenhall, W. C., Nat Geog. Mag., Vol. XIV, 1903, pp. 395-407. Moffit, F. H. and Maddren, A. G., Bull. 374, U. S. Geol. Survey, 1909, pp. 37-42, and map, Pis. I, H. Dunn, Robert, Harper's Magazine, Vol. XCVH[, 1909, pp. 479-509. Capps, S.R., Journ, Geol., Vol. XVHI, 1910, pp. 83-67; Science, N. S., Vol. 30,1909, p. 974; Journ. Geol., Vol. XVm, 1910, pp. 359-875; Bull. 417, U. S. Geol. Survey, 1910, pp. 36-42. See also photographs, Nat. Geog. Mag., Vol. XX, 1909, pp. 612, 617, 618, 620, 621. *Bull. 448, U. S. Geol. Survey, 1911, PL H and pp. 43-59. • Keen, Dora, Scribner's Magazine, Vol. 52, 1912, pp. 64-80; Ladies' Home Journal, Vol. 80, August, 1913, p. 7.